Blame it (on the sulfide)

Darn that H2S, it makes twisted abominations of everything!

Before

After spending 17 days in the sulfide seep, the previously “clean” and bacteria free crabs look drastically different. Once a dark green with a smooth body (with the exception of already slightly hairy legs), the crabs are now very white and fairly “yeti”-like. Their whole bodies are covered with bacteria. Using my simple scale (0-5) for rating the bacteria on these crabs from the sulfide seeps, these crabs would be a 5. With all the bacteria on them, they really do look like twisted abominations.

After 17 days

These crabs have survived better than expected though. I really wasn’t expecting them to still be alive after all this time; I honestly thought they would perish sooner because, unlike the crabs that live there freely, they are confined to staying in the sulfide seep. Also, it doesn’t take too long for the bacteria to start colonizing on the crabs. On the third day, there was at least one strand of bacteria on one of the crabs. So far, only a couple of the crabs being kept in the sulfide seep have expired, though it could possibly have been more if one of my containers hadn’t mysteriously disappeared. Whether the crabs rely on the bacteria to survive in the sulfide isn’t clear, however.

The other tests I have been running have also been going well. Since I’ve decided to use 5 crabs at a time for habitat choice trials, I have greatly increased my sample size. It seems that the crabs (regardless of where I collected them from) prefer the clean water to the sulfide water. Next week, I will be providing a rock in the sulfide side to see whether the presence of a shelter could change the crabs’ preference.

The race trials have also been going well; it seems that crabs generally run faster in clean water than in sulfide water, and crabs from sulfide seeps tend to be faster than crabs from clean areas in sulfide water. I’ve also started to sample another sulfide seep further along Ruston Way. Though there isn’t a stream of water at this site, there is still a large amount of bacteria present on rocks and crabs found there.

I’ve also been getting a lot more exercise this summer.

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